arXiv: Algebraic Geometry最新文献

筛选
英文 中文
Almost nef regular foliations and Fujita's decomposition of reflexive sheaves 几乎非正则叶理和自反束的Fujita分解
arXiv: Algebraic Geometry Pub Date : 2020-07-28 DOI: 10.2422/2036-2145.202010_055
M. Iwai
{"title":"Almost nef regular foliations and Fujita's decomposition of reflexive sheaves","authors":"M. Iwai","doi":"10.2422/2036-2145.202010_055","DOIUrl":"https://doi.org/10.2422/2036-2145.202010_055","url":null,"abstract":"In this paper, we study almost nef regular foliations. We give a structure theorem of a smooth projective variety $X$ with an almost nef regular foliation $mathcal{F}$: $X$ admits a smooth morphism $f: X rightarrow Y$ with rationally connected fibers such that $mathcal{F}$ is a pullback of a numerically flat regular foliation on $Y$. Moreover, $f$ is characterized as a relative MRC fibration of an algebraic part of $mathcal{F}$. As a corollary, an almost nef tangent bundle of a rationally connected variety is generically ample. For the proof, we generalize Fujita's decomposition theorem. As a by-product, we show that a reflexive hull of $f_{*}(mK_{X/Y})$ is a direct sum of a hermitian flat vector bundle and a generically ample reflexive sheaf for any algebraic fiber space $f : X rightarrow Y$. We also study foliations with nef anti-canonical bundles.","PeriodicalId":278201,"journal":{"name":"arXiv: Algebraic Geometry","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134192959","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 3
Fields of definition of elliptic fibrations on covers of certain extremal rational elliptic surfaces 某些极值有理椭圆曲面盖上椭圆纤振的定义域
arXiv: Algebraic Geometry Pub Date : 2020-07-28 DOI: 10.14288/1.0396004
Victoria Cantoral Farf'an
{"title":"Fields of definition of elliptic fibrations on covers of certain extremal rational elliptic surfaces","authors":"Victoria Cantoral Farf'an","doi":"10.14288/1.0396004","DOIUrl":"https://doi.org/10.14288/1.0396004","url":null,"abstract":"We study K3 surfaces over a number field $k$ which are double covers of extremal rational elliptic surfaces. We provide a list of all elliptic fibrations on certain K3 surfaces together with the degree of a field extension over which each genus one fibration is defined and admits a section. We show that the latter depends, in general, on the action of the cover involution on the fibers of the genus 1 fibration.","PeriodicalId":278201,"journal":{"name":"arXiv: Algebraic Geometry","volume":"103 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114580688","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Elliptic classes on Langlands dual flag varieties 在朗兰双旗变种上的椭圆形类
arXiv: Algebraic Geometry Pub Date : 2020-07-17 DOI: 10.1142/S0219199721500140
Richárd Rimányi, Andrzej Weber
{"title":"Elliptic classes on Langlands dual flag varieties","authors":"Richárd Rimányi, Andrzej Weber","doi":"10.1142/S0219199721500140","DOIUrl":"https://doi.org/10.1142/S0219199721500140","url":null,"abstract":"Characteristic classes of Schubert varieties can be used to study the geometry and the combinatorics of homogeneous spaces. We prove a relation between elliptic classes of Schubert varieties on a generalized full flag variety and those on its Langlands dual. This new symmetry is only revealed if Schubert calculus is elevated from cohomology or K theory to the elliptic level.","PeriodicalId":278201,"journal":{"name":"arXiv: Algebraic Geometry","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121828020","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 7
Affine Pavings of Hessenberg Ideal Fibers 海森伯格理想纤维的仿射铺装
arXiv: Algebraic Geometry Pub Date : 2020-07-17 DOI: 10.13016/EVQM-0Y32
Ke Xue
{"title":"Affine Pavings of Hessenberg Ideal Fibers","authors":"Ke Xue","doi":"10.13016/EVQM-0Y32","DOIUrl":"https://doi.org/10.13016/EVQM-0Y32","url":null,"abstract":"We define certain closed subvarieties of the flag variety, Hessenberg ideal fibers, and prove that they are paved by affines. Hessenberg ideal fibers are a natural generalization of Springer fibers. In type $G_2$, we give explicit descriptions of all Hessenberg ideal fibers, study some of their geometric properties and use them to completely classify Tymoczko's dot actions of the Weyl group on the cohomology of regular semisimple Hessenberg varieties.","PeriodicalId":278201,"journal":{"name":"arXiv: Algebraic Geometry","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132825011","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 3
Sheaf Theoretic Compactifications of the Space of Rational Quartic Plane Curves 有理四次平面曲线空间的束理论紧化
arXiv: Algebraic Geometry Pub Date : 2020-07-15 DOI: 10.11650/TJM/210103
Kiryong Chung
{"title":"Sheaf Theoretic Compactifications of the Space of Rational Quartic \u0000 Plane Curves","authors":"Kiryong Chung","doi":"10.11650/TJM/210103","DOIUrl":"https://doi.org/10.11650/TJM/210103","url":null,"abstract":"Let $R_4$ be the space of rational plane curves of degree $4$. In this paper, we obtain a sheaf theoretic compactification of $R_4$ via the space of $alpha$-semistable pairs on $mathbb{P}^2$ and its birational relations through wall-crossings of semistable pairs. We obtain the Poincare polynomial of the compactified space.","PeriodicalId":278201,"journal":{"name":"arXiv: Algebraic Geometry","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121880931","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
The fibers of the ramified Prym map 分叉的Prym图的纤维
arXiv: Algebraic Geometry Pub Date : 2020-07-04 DOI: 10.1142/S0219199721500309
P. Frediani, J. Naranjo, I. Spelta
{"title":"The fibers of the ramified Prym map","authors":"P. Frediani, J. Naranjo, I. Spelta","doi":"10.1142/S0219199721500309","DOIUrl":"https://doi.org/10.1142/S0219199721500309","url":null,"abstract":"We study the ramified Prym map $mathcal P_{g,r} longrightarrow mathcal A_{g-1+frac r2}^{delta}$ which assigns to a ramified double cover of a smooth irreducible curve of genus $g$ ramified in $r$ points the Prym variety of the covering. We focus on the six cases where the dimension of the source is strictly greater than the dimension of the target giving a geometric description of the generic fibre. We also give an explicit example of a totally geodesic curve which is an irreducible component of a fibre of the Prym map ${mathcal P}_{1,2}$.","PeriodicalId":278201,"journal":{"name":"arXiv: Algebraic Geometry","volume":"53 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123870122","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 5
Determinantal tensor product surfaces and the method of moving quadrics 行列式张量积曲面及移动二次曲面的方法
arXiv: Algebraic Geometry Pub Date : 2020-06-30 DOI: 10.1090/tran/8358
Laurent Bus'e, Falai Chen
{"title":"Determinantal tensor product surfaces and the method of moving quadrics","authors":"Laurent Bus'e, Falai Chen","doi":"10.1090/tran/8358","DOIUrl":"https://doi.org/10.1090/tran/8358","url":null,"abstract":"A tensor product surface $mathcal{S}$ is an algebraic surface that is defined as the closure of the image of a rational map $phi$ from $mathbb{P}^1times mathbb{P}^1$ to $mathbb{P}^3$. We provide new determinantal representations of $mathcal{S}$ under the assumptions that $phi$ is generically injective and its base points are finitely many and locally complete intersections. These determinantal representations are matrices that are built from the coefficients of linear relations (syzygies) and quadratic relations of the bihomogeneous polynomials defining $phi$. Our approach relies on a formalization and generalization of the method of moving quadrics introduced and studied by David Cox and his co-authors.","PeriodicalId":278201,"journal":{"name":"arXiv: Algebraic Geometry","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121310917","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 5
Mirror Symmetry and smoothing Gorenstein toric affine 3-folds 镜面对称与平滑Gorenstein环仿射三折
arXiv: Algebraic Geometry Pub Date : 2020-06-30 DOI: 10.1017/9781108877831.005
A. Corti, Matej Filip, Andrea Petracci
{"title":"Mirror Symmetry and smoothing Gorenstein toric affine 3-folds","authors":"A. Corti, Matej Filip, Andrea Petracci","doi":"10.1017/9781108877831.005","DOIUrl":"https://doi.org/10.1017/9781108877831.005","url":null,"abstract":"We state two conjectures that together allow one to describe the set of smoothing components of a Gorenstein toric affine 3-fold in terms of a combinatorially defined and easily studied set of Laurent polynomials called 0-mutable polynomials. We explain the origin of the conjectures in mirror symmetry and present some of the evidence.","PeriodicalId":278201,"journal":{"name":"arXiv: Algebraic Geometry","volume":"79 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126190316","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 6
K3 carpets on minimal rational surfaces and their smoothings K3地毯在最小的有理表面及其平滑
arXiv: Algebraic Geometry Pub Date : 2020-06-30 DOI: 10.1142/S0129167X21500324
Purnaprajna Bangere, Jayan Mukherjee, D. Raychaudhury
{"title":"K3 carpets on minimal rational surfaces and their smoothings","authors":"Purnaprajna Bangere, Jayan Mukherjee, D. Raychaudhury","doi":"10.1142/S0129167X21500324","DOIUrl":"https://doi.org/10.1142/S0129167X21500324","url":null,"abstract":"In this article, we study K3 double structures on minimal rational surfaces $Y$. The results show there are infinitely many non-split abstract K3 double structures on $Y = mathbb{F}_e$ parametrized by $mathbb P^1$, countably many of which are projective. For $Y = mathbb{P}^2$ there exist a unique non-split abstract K3 double structure which is non-projective (see Drezet's article in arXiv:2004.04921). We show that all projective K3 carpets can be smoothed to a smooth K3 surface. One of the byproducts of the proof shows that unless $Y$ is embedded as a variety of minimal degree, there are infinitely many embedded K3 carpet structures on $Y$. Moreover, we show any embedded projective K3 carpet on $mathbb F_e$ with $e<3$ arises as a flat limit of embeddings degenerating to $2:1$ morphism. The rest do not, but we still prove the smoothing result. We further show that the Hilbert points corresponding to the projective K3 carpets supported on $mathbb{F}_e$, embedded by a complete linear series are smooth points if and only if $0leq eleq 2$. In contrast, Hilbert points corresponding to projective K3 carpets supported on $mathbb{P}^2$ and embedded by a complete linear series are always smooth. The results in an a recent paper of Bangere-Gallego-Gonzalez show that there are no higher dimensional analogues of the results in this article.","PeriodicalId":278201,"journal":{"name":"arXiv: Algebraic Geometry","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123819062","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 4
Spectral interpretations of dynamical degrees and applications 动态度的光谱解释及其应用
arXiv: Algebraic Geometry Pub Date : 2020-06-18 DOI: 10.4007/annals.2021.194.1.5
Nguyen-Bac Dang, C. Favre
{"title":"Spectral interpretations of dynamical degrees and\u0000 applications","authors":"Nguyen-Bac Dang, C. Favre","doi":"10.4007/annals.2021.194.1.5","DOIUrl":"https://doi.org/10.4007/annals.2021.194.1.5","url":null,"abstract":"We prove that dynamical degrees of rational self-maps on projective varieties can be interpreted as spectral radii of naturally defined operators on suitable Banach spaces. Generalizing Shokurov's notion of b-divisors, we consider the space of b-classes of higher codimension cycles, and endow this space with various Banach norms. Building on these constructions, we design a natural extension to higher dimension of the Picard-Manin space introduced by Cantat and Boucksom-Favre-Jonsson in the case of surfaces. We prove a version of the Hodge index theorem, and a surprising compactness result in this Banach space. We use these two theorems to infer a precise control of the sequence of degrees of iterates of a map under the assumption that the square of the first dynamical degree is strictly larger than the second dynamical degree. As a consequence, we obtain that the dynamical degrees of an automorphism of the affine 3-space are all algebraic numbers.","PeriodicalId":278201,"journal":{"name":"arXiv: Algebraic Geometry","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128782935","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 19
0
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
确定
请完成安全验证×
相关产品
×
本文献相关产品
联系我们:info@booksci.cn Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术官方微信